Conventional antiperspirants comprising salts of aluminum or aluminum/zirconium are known. These salts function as antiperspirants by forming polymeric complexes which can plug pores, thereby blocking sweat release. There is a need for additional antiperspirant active agents that provide complexes of a size capable of plugging pores to block sweat, that provide deodorant/antibacterial efficacy, and that are less irritating to the skin than the acidic salts in conventional antiperspirants. There is also a need for alternative antibacterial and skin protective agents for use in liquid hand soaps and body washes. Finally, there is a need for agents in oral care products which can whiten and strengthen teeth, retard erosion, and inhibit bacteria and plaque.
Some tetrabasic zinc-amino acid complexes, however, do not have the most optimal precipitation kinetics. In another words, their rate of precipitation upon dilution may be too slow or too fast for typical applications. For example, for oral care typical recommended brushing times range from 1 minute to 3 minutes, but an average person brushes for a significantly shorter duration. Typical recommended rinsing times with a mouthrinse is about a minute, but an average person spends much less time.
Therefore, there exists a need for optimizing the precipitation times of tetrabasic zinc halide-amino acid complexes. In particular, there is a need for reducing or delaying the precipitation times associated with the tetrabasic zinc halide-amino acid complexes.